Pattern for vertical casting systems



y 1953 w. H. JOHNSON 2,645,829

PATTERN FOR VERTICAL CASTING SYSTEMS Filed May 4, 1950 2 INVENTORWILLIAM H. JOHNSON BY a" ATTORNEYJ Patented July 21, 1953.

UNITED STATES PATENT OFFICE 2,645,829 r I l PATTERN FOR VERTICAL CASTINGSYSTEMS William H'. Johnson, Washington, D. C. Application May 4, 1950,Serial No. 159,909

(Cl. 22-157) (Granted/under Title 35, U. s. Code (1952),

2 Claims.

sec. 266) This invention relates toimprovements in the casting ofmetals, more patricularly to new systems for the pouring of metal invertical casting and to match plates for the molding of foundry coreswhich in the set up position in'the foundry flask delineate or embodythe new pouring systems of the invention.

Vertical casting as'commonly carried out inthe foundry involves a systemincluding a vertical conduit or sprue with which is connected aseries ofhorizontally arranged conduits, usually two, lying one above the other,called step gates, which lead into the casting cavity. The pouringsystem which is located in the foundry flask adjacent the castingcavity, is defin d by forms which carry on their opposing faces,a mirrorhalf of the sprue and the step gates; In operation of the system,

the metal is poured into the sprue and enters through the first orlowermost step gate into the casting cavity. When the level of the metalin the casting cavity reaches the point of entry of'thez 1 next higherstep gate, flow of the metal from the sprue into the casting cavitytakes place through this step gate, also. This is known in the art assequence flow of the metal into the'casting cavity.

It has the advantages of shortening the pouring time and tending toproduce 1 sounder castings. However, with asingle known exceptionbased'upon a particularmetal, experience has shown that sequence flow ofthe metal in vertical casting systems can be had only with two stepgates no,

flow or only a dribbling of the metal into the casting cavity being had"through the third'step gate. In view of the advantages to be derivedtherefrom, it is obviously, desirable to have a pouring system in whichsequence flow of metals generally can;

be had through threerather than only two step gates, especially for the.founding of the longer castings.

It is, accordingly, an object of the present inventionto provide animproved system for the pouring of metals generally in vertical castingin which sequence flow into the casting cavity can be had through threestep gates.

It is a further object of the invention to provide match plates fromwhich can be molded? foundry forms which when set up in 'the foundryflask define the metal pouring systems of the invention.

Other objects of the invention will become apparent from the descriptionwhich follows:

Briefly stated, I have found that metals generally can be induced toflow sequentially through each of three step gates into the castingcavity of a vertical casting system by providing in combination, avertical conduit or sprue, a reservoir connected therewith and with asecond vertically 2' arranged conduit or reverse sprue,;and a-seriesofthree step gates connected to the reverse sprue and leading into thecasting cavity. a I In th other aspect of my invention I have'providedmatch plates for the new pouring systems from which, in the usual way,can be molded matching foundry cores-which in their juxtaposed oroperative position in the foundryflaskv define or delineate the newpouring systems. These match plates carry'on a broad. face thereof, araised design in half longitudinal section-of the new pouringsystems,-the raised design taking the form of a series of interconnectedbossesfin half longitudinal section of th several parts of, the pouringsystem.

The invention will be more fully understood by reference to thefollowing description taken in conjunction with the accompanying drawingin which like parts carry like numerals and in which: Figure 1 is aperspectivev view of :a match plate carryinga raised design fora-pouringsystem in connected a reverse sprue 3. 4, 5 'and'G- are step.

gates connected with the reverse sprue 3 and leading-into the castingcavity 1 shown in conventionalized form. 1 I

Th sprues and step gates are of equal diameter. The reservoir 2. asshown, is. of circular crosssection but may be ofany other configurationfound-suitable, such as'rectangular 0r.0b10id,'pr0- vided it hassuflicient capacity to reduce to a substantial degree the momentum ofthe metal flowing into it from the sprue I. The depth of the reservoirshould be at least equal in magnitude to'the-diameter of the sprue l andpreferably is greater,for'example, two to three times greater. Th widthof the reservoir may be of'about the same magnitude as its depth and thelength thereof should be sufficient to at least accommodate the sprues Iand 3 connected in side by side rela: tionship to the top of thereservoir, but preferably is slightly greater.

In operation of the pouring system shown in Figure 1A, the metal, forexample, steel, is poured into the sprue l, filling the reservoir 2. Thereservoir serves to substantially reduce the momentum of the metalarriving from the sprue I. The metal rises upwardly from the reservoirinto flows from the reverse sprue 3 into the casting cavity 1 throughstep gate 6 -.to completecasting of the metal.

Figure 2A shows a pouring systems'imilarfir'iutached thereto, said shortvertical boss having a length and depth equal to from twice to threetimes the magnitude of the diameter of said first vertical half-roundboss, said tapered vertical half-round boss having a minimum cross-sec-.tion'al area equal to that 'of said first vertical all respects to thatshown in Figure l awith the. exception that the reverse sprue 8is"taperedin' cross-section and connected at its basezwith'the reservoir2. The step gates 4, Sand S are connected to the vertical side 6 of thetapered re" The operation of the system is" verse sprue 8. the same asthat of Figure 1A. The enlargement of the base of the reverse 'sp'rue 8serves to further reduce the momentum of the metal whereby Spurting ofthe metal into the casting mold 1 through the second step gate -isminimized or avoided. At the top, the cross-sectional area of thetapered sprue B is equal to that of the sprue I and at the bottom it'canbe from about two to four'times the same;

In Figure 1 match plate In is provided with a raised design in halflongitudinal section of the pouring system shown in Figure 1A, and inFigure 2 match plate II is shown provided with a similar raised designof the pouring system of Figure 2A. The raised designs are constitutedby a series of connected bosses which are identified with therespective'elements of the pouring systerns by means of like numerals.The match 7 plates may bemade of wood, metal or other suitablematerial'and the raised designprovided thereon in known manner. v

Since various modifications and changes may be made in the inventionwithout departing from the spirit or the scope thereof, itis notintended that it shall be limited to the herein described specificembodiments thereof but only as is required' by the appended claims.

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

What is claimed is: i

1. A pattern plate for molding foundry pouring forms, said pattern platehaving attached to half-round boss and a maximum cross-sectional area offrom about two to four times the same,

a series of three horizontal bosses attached to said tapered verticalboss along the side thereof which is remote from the adjacent vertical 1boss and so arranged therealong that the lowermost of the three islocated at the lower end and 'the-hi'ghest' at the upper end thereof,and the second is located intermediate of the other two, each of saidthree horizontal bosses having a cr'oss sectional area equal to that ofsaid first vertical half-round boss.

2. A foundry pattern for molding pouring forms, said pattern comprising.a system of solid elements having a'flat surface each of which lies in acommon plane, said system of solid elements including a short verticalbar of generally'rectangular' cross section having its outer verticaledges rounded off-,a pair of adjacently disposed verticalhalf-cylinders, the first of which is longer than the second, the secondis of upwardly tapering cross-section and both are of greater lengththan said short vertical bar, each of said pair of verticalhalf-cylinders being attached at its lower end to the upper horizontalface of said short vertical bar, said horizontal face having a widthslightly greater than is necessary to accommodatethe ends of said pairof vertical halfcylinders attached thereto, .said short vertical barhaving a length and depth equal to from twice to three times themagnitude of the diameter of said first vertical half-cylinder,'saidtapered vertical half-cylinder having a minimum crosssectional areaequal to'that of said first vertical half-cylinder and a maximumcross-sectional area of from about twotofour times the same.

a series of three horizontal half-"cylinders attached to said taperedvertical half-cylinder along the side thereof which is remote from theadjacent vertical half-cylinder andso arranged therealong that thelowermost of the three is al area equal to'that of said first verticalhalfa broad face thereof a system of bosses including a a short verticalboss of generally'rectangular cross-section having its outer verticaledges rounded off, a pair of adjacentl disposed vertical half-roundbosses, the first of which is longer than the second, the second is ofupwardly tapering cross-section and both are of greater length than saidshort vertical boss, each of said pair of vertical bosses being attachedat its lower end to the upper horizontal face of said short verticalboss, said horizontal face having a width slightly greater than isnecessary to accommodate the ends of said pair of vertical bossesatcylinder.

WILLIAM H. JOHNSON.

References Cited in the file of this patent UNITED STATES PATENTSclusive, and 252.

